**Persistent low-pressure trough and nearby tropical cyclone activity are the main drivers keeping minimum temperatures around 26–27°C on August 24, with closely matched market odds reflecting forecast uncertainty in overnight cooling.** Hong Kong Observatory guidance for August 24 projects a range of 27–31°C amid cloudy conditions, occasional showers, and squally thunderstorms linked to a broad trough and Tropical Cyclone Zitan lingering near the northern South China Sea before potentially tracking toward western Guangdong. South to southwest winds of 4–5 (locally 6 on high ground) and high humidity (75–95%) limit nocturnal radiative cooling, while sea-surface temperatures near 27°C provide a warm baseline. Multiple models and ensembles show slight divergence on cloud cover and rainfall timing, which can raise or lower the overnight low by 1°C depending on how effectively showers suppress temperature drops. Historical late-August minima in Hong Kong typically fall in the mid-26°C range under similar disturbed monsoon patterns, supporting the tight clustering between 26°C and 27°C in trader positioning. Key upcoming catalysts include the next HKO 9-day bulletin, updated regional model runs, and any revisions to Zitan’s track or intensity that could alter wind, cloud, or precipitation forecasts for the overnight period.